Boat-lowering gear.



. Patented Feb. 26, l90l. n. ROCHE. BOAT LOWEBING GEAR.

(Application filed June 19 1900; '(No Mudgl.)

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Np. 668,660. Patented Feb. 26, MN.

D. ROCHE.

' BOAT LOWERI'NG GEAR.

(Application filed June 19, 1900.; (No Model.) 3 Sheets8heat 2.

D. ROCHE.

BOAT LOWERING GEAR.

(Applicaticnfiled June 19,1900;

No."66 8,660. A Patehted Feb 26, l90l.

(No Ilpdal.)

3 Sheets-Sheet 3,

UNITED STATES PATENT OFFICE.

DAVID ROCHE, OF LONDON, ENGLAND.

BOAT-LOWERING G EAR.

SPECIFICATION forming part of Letters Patent No. 668,660, dated February26, 1901.

Application filed June 19, 1900- Serial No. 20,891. (No model.)

T0 at whom, it may concern:

Be it known that I, DAVID ROCHE, a subject of the Queen of England,residing at London, England, have invented certain new and usefulImprovements in or Relating to Boat- Lowering Gear, of which thefollowing is a specification.

This invention relates to boat-lowering gear, and has for its object theprovision of means for adjusting the devices of a kind hereinafterdescribed by which the movement of pivoted davits outboard is retardedmore or less, as desired. Such adjustment is necessary when the shipheels or acquires a list, for under such circumstances the action ofthese retarding devices as heretofore arranged is inconvenientlymodified by alteration of the trim of the vessel.

Boat-lowering gear has been made'in which the weight of the davits wheninclined outboard has been balanced by means of a weighted roller orother traveling strut situated in the angle between the davit and afixed inclined guide; but this arrangement operating in the mannerhereinafter described has the defect of not being in balance should theship have a list to either side. According to the present invention thisdifficulty is obviated by making the inclined guides adjustable asregards the angle they make with the davits and the deck, so that thedavits and the boat may be wholly or partially balanced as regards theirweight irrespectively of the list of the ship. Moreover, itwill be seenfrom what follows that the inclined guides can be made to extendsufficiently far over the vessels side to act as an outrigger by whichthe boat can be pulled out with the aid of a tackle attached to theoutboard portion of the inclines. Further, the inclined guides when thusextended beyond the ships side afford, together with the traveling strutrun out to their ends, an outboard-support for the davitintermediate ofits ends, so that the excessive bending moment which would otherwisecome upon the davits in their extreme outboard position, if no suchsupport were provided, is materially counteracted.

-Whether the inclined track be so far inclined as to project over theships side or not, it is desirable that it should be so adjusted thatwith the davits in their extreme position and the boat ready forlowering the traveling strut should be at the end of the incline. Bythis means the maximum support for the davit is obtained in any case.

In the accompanying drawings, which illustrate one method of applyingthis invention, Figure 1 is a perspective view of the boatlowering gearwith boat in place. Fig. 2 is an end view of the gear with boat readyfor lowering, the ship having a list, as shown. Fig. 3 is also an endview of the geanwith boat ready for lowering, but with the ship listedin a direction opposite to that indicated by Fig. 2.

Like letters indicate like parts throughout the drawings.

A represents davits pivoted to the deck at A. At B, also pivoted to thedeck, are inclined guides B, which arejoined at their upper ends by abar B 0 represents holes in beams G to enable the inclined guides B tobe fixed at various degrees of inclination by means of pins 0 '0represents bolts for locking the davits A to the beams 0 when the boat Jis in the chocks L.

D represents rollers constituting traveling struts and borne on an axleD, which move up the inclined guides B when the davits A are cantedoutboard.

E is a tackle for canting the davits A out-- board when the guides Bhave been secured to the beams O or for raising the guides B when thedavits A are clamped to the beams O.

F is a tackle for operating the inclined guides B.

G is another tackle for pulling the axle D, on which are mounted therollers D, downward.

Ties H may be provided between the beams O and the inclined guides B topartly support the Weight of the gear and a boat J when placed in theirextreme outboard position, as shown in Fig. 2.

K is a tackle for hoisting or lowering the boat J.

L represents chocks for the boat J to rest on when it is in the positionshown in Fig. 1.

The operation of this known type of. boatlowering gear is as follows,presuming the boat J to be in position onthe chocks L, as shown in Fig.1, and that it is required to inby means of the bolts 0 cline the davitsA outboard preparatory to lowering the boat J: The boat J is let go byslipping the chocks out. As the center of gravity of the gear isslightly on the outboard side of the pivots A, on releasing the tackle Gthe davits A, together with the boat J, will move outboard, the speedwith which they travel being checked by the weighted rollers D, whichare at the same instant forced in an upward and outboard directionbetween the davits A and the inclined guides B until the boat J isbrought into a position in which it is ready for lowering. Thisoperation can be satisfactorily repeated as long as the vessel does notheel. Difficulty has, however, been experienced when the vessel heels,as, on the one hand,when the inclined guides B approach the horizontalthe weight of the davits A and the boat J will overcome the retardingeffect of the rollers D owing to the center of gravity of the gear beingfarther on the outboard side of the pivots A than before and also owingto the incline up which the weighted rollers D travel having a smallerangle with the horizontal plane than before. On the other hand, when theinclined guides B approach the vertical the center of gravity of thegear will be brought to the inboard side of the pivots A and the inclineup which the weighted rollers travel will have a greater angle with thehorizontal than before. Consequently the retarding effect which therollers exert on the davits A and the boat J will be increased. In theconstruction illustrated according to this invention this difficulty isovercome by pivoting the inclined guides B to the deck at B, so thatthey maybe set at various degrees of inclination, being retained in thepositions required by fixing them to the beams O by means of the pins 0Thus should the ship have a list to either side, and consequently theaction of the rollers D relatively to the davits A be modified, asheretofore shown, the gear may be adjusted again by altering theinclination of the guides B either one way or the other, according towhich side the ship is listed. The inclination of the guides B may bealtered by operating the tackle E, F, or G, the davits A first beingfixed to the beam G The guides B having been altered to the desiredinclination and fixed in relation to the beam 0 by the pins and thedavits A having been released from the beam 0, the davits A, togetherwith the boat J, may now be canted outboard and the boat J made readyfor lowering, as hereinbefore described.

From the foregoing it will be seen that when the ship has a weather listthe inclines can be lowered to lessen the drag of the traveling strutswhich is exerted when the boat is pulled over the higher side of theship.

On the other hand, when the ship has a lee list the inclines are raisedto increase the drag of the traveling strut and to be of greater supportto the davits. Moreover, with a lee list the boat when my invention isemployed is kept nearer to the 'ships side than would be possible withany other type of boat-low- .ering gear with which I am acquainted, and

this facilitates the safe shipment of passengers.

It will be seen that without departing from the nature of the inventiondifferent methods from those shown in the accompanying drawings may beused for raising or lowering the inclined guides B or the rollers D-as,for instance, in place of the tackle E, F, or G a worm and worm-wheelmay be used or the position of theinclined guidesB may be altered bymanual labor instead of by a mechanical device. Again, other devicesthan those shown may be used for relatively fixing the davits A or theguides B to the beam 0.

What I claim as my invention, and desire to secure by Letters Patent, is

1. In a boat-lowering gear the combination with a davit hinged at itsheel to the deck, a track inclined upward and outboard from the lowerportion of the davit and adjustable as to its degree of inclination tothe davit, means to retain the track in positions to which it is thusadj ust-able, and a traveling strut, situated in the angle between thetrack and the davit, substantially as set forth.

2. In a boat-lowering gear the combination with a davit hinged at itsheel to the deck, a track inclined upward and outboard from the lowerportion of the davit and adjustable as to its degree of inclination tothe davit, means to retain the track in positions to which it is thusadjustable, means to lock the davit a tackle secured at one end to thetrack and at the other end to the davit, and a traveling strut situatedin the angle between the track and the davit substantially as set forth.

3. In a boat-lowering gear the combination with a davit hinged at itsheel to the deck, of a track inclined upward and sufficiently long to beable to project beyond the ships side, adjustable as to its degree ofinclination to the davit, means to retain the track in positions towhich it is thus adjustable, and a traveling strut situated in the anglebetween the track and the davit and movable to the extreme upper end ofthe track for the purpose set forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

DAVID ROCHE.

Witnesses:

HARRY B. BRIDGE, T. G. GLADWIN.

